The invention relates to a container for molten metals with a temperature measuring device arranged in an opening of a container wall, wherein the temperature measuring device has a protective sheath, which projects into the container and which is closed at its end arranged in the container, and a temperature measuring element arranged in an opening of the protective sheath. In addition, the invention relates to the use of the container, as well as to a method for determining an interface between two materials arranged one above the other in a container, particularly between a slag layer and underlying steel melts.
Such containers are known from the prior art. For example, it is known from German Utility Model GM 72 28 088 to arrange a thermocouple in a wall of a steel ladle. The thermocouple is arranged in a steel tube, which is surrounded by a ceramic protective layer. German Patent DE 1 054 735 discloses a smelting crucible for metals, in whose side wall a temperature sensor is inserted. The temperature sensor has a protective tube made of a metal-ceramic material, such as molybdenum and aluminum oxide. The protective tube projects with its tip approximately 25 mm into the side of the smelting space. U.S. Pat. No. 3,610,045 discloses a smelting crucible for molten iron, in whose side wall a thermocouple is arranged. The thermocouple is protected by a conical protective sheath made of aluminum oxide and silicon oxide. A similar container is known from European Patent EP 314 807 B1. Also in this container, a thermocouple is led through the wall into the interior of the container. The thermocouple is protected by an aluminum oxide tube which, in turn, is surrounded by a boron nitride protective sheath in the interior of the container.
From U.S. Pat. No. 6,309,442 B1 a container for molten metals is known, on whose inner side contacts made of zirconium dioxide or thorium dioxide are arranged one above the other, in order to measure the level of the interface between the molten metal and the slag.